The 1998–99 UEFA Champions League was the 44th season of the UEFA Champions League, Europe's premier club football tournament, and the seventh since it was renamed from the "European Champion Clubs' Cup" or "European Cup". The competition was won by Manchester United, coming back from a goal down in the last two minutes of injury time to defeat Bayern Munich 2–1 in the final. Teddy Sheringham and Ole Gunnar Solskjær scored United's goals after Bayern had hit the post and the bar. They were the first English club to win Europe's premier club football tournament since 1984 and were also the first English club to reach a Champions League final since the Heysel Stadium disaster and the subsequent banning of English clubs from all UEFA competitions between 1985 and 1990. It was the first time since 1968 that Manchester United won the Champions League, giving them their second title.

Manchester United also completed the Treble, becoming the fourth side in Europe to do so and in the process prevented Bayern Munich from achieving the feat themselves, Bayern eventually finished runners-up in their domestic cup two weeks later.

1998–99 UEFA Champions League

Manchester United won the trophy without losing a single match, despite having competed in a group with Bayern Munich, Barcelona and Brøndby, plus two highly rated Italian clubs in the knock-out stages. However, United became champions with just five wins in total, the lowest number of wins recorded by a champion in the Champions League era to date, though the competition now has an extra round of two matches in the knock-out stages.

1998–99 UEFA Champions League

It was the first time the Champions League was won by a team that had neither won their domestic league nor the Champions League the previous season and therefore would not have qualified for the tournament under the old qualification rules (title holder or national league champion). For the second time, the runners-up of eight domestic leagues entered the competition.

1998–99 UEFA Champions League

Real Madrid were the defending champions but were eliminated in the quarter-finals by Dynamo Kyiv.

Association team allocation

Number of teams per country as well as the starting round for each club and seeding were based on 1998 UEFA league coefficient, which takes into account their performance in European competitions from 1993–94 to 1997–98. Associations ranked 1–8 each have two participants Associations ranked 9–48 each have one participant (except Liechtenstein)

Teams

Round and draw dates

The schedule of the competition is as follows (all draws are held in Geneva, Switzerland, unless stated otherwise).

Qualifying rounds

First qualifying round

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Second qualifying round

Losing teams qualified for the first round of the 1998–99 UEFA Cup.

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Note: Winning teams of the first qualifying round were drawn against teams qualified directly for the second qualifying round (16 and 16 teams).

This match was played at Naftex's Neftochimik Stadium in Burgas because Litex Lovech's Lovech Stadium in Lovech did not meet UEFA standards. This match was played at FK Partizan's Partizan Stadium in Belgrade because FK Obilić's Miloš Obilić Stadium in Belgrade did not meet UEFA standards.

Group stage

Twenty-four teams took part in the group stage: the national champions of Italy, Germany, Spain, France, Netherlands, England and Portugal, the title holders, and the 16 winning teams from the second qualifying round. Arsenal, Athletic Bilbao, Brøndby, Croatia Zagreb, HJK, Internazionale, Kaiserslautern, Lens and Sturm Graz made their debuts in the group stage of the competition. This was the first time that a team from Finland played in the group stage. Spain became the first association to have three teams in the Champions League group stage.

The teams were divided into six groups of four teams each, with the teams in each group playing each other twice (home and away) in a double round-robin format. Three points were awarded for each win, with one point each for a draw and none for a defeat. The winners of each group progressed to the quarter-finals, along with the two best second-placed teams. In the event that two or more teams had the same number of points at the end of the group stage, the rankings of the teams in question were determined by the following criteria: greater number of points obtained in the matches between the teams in question goal difference resulting from the matches between the teams in question greater number of goals scored away from home in matches between the teams in question superior goal difference from all the matches played greater number of goals scored national association's coefficient at the start of the season in question